[Amps] Tuned Input

[Ian White, GM3SEK]

Peter Chadwick wrote:
>> From memory, didn't some of the Collins amplifiers specify a
>> certain length of coax to go between exciter and amplifier to get
>> the total phase shift right on all bands? i.e. to reflect an
>> impedance such that as far as the GG amp was concerned, it was fed
>> from low impedance voltage source.


Yes, they did, but that recommendation didn't rule out the use of a 
pi-tank. In the first edition of 'SSB Principles and Circuits', the 
Collins authors show a driver with an output pi-tank, the magic length 
of line and a pi-tank input on the amplifier. They didn't say how you're 
supposed to switch bands, though.



> 73 Peter SM/G3RZP This week - W6 next week!)

73 from
Ian G/GM3SEK until Wednesday
and after that, it'll be "GM3SEK" for good!